Clothing, in particular, outer clothing such as a windbreaker, a down jacket, down wear, and rainwear may be fluffed or torn in a side or shoulder portion by being put on or by being rubbed against a rucksack or the like in the case of, for example, the rucksack being carried on the back. Particularly, in recent years, the weight of down wear is becoming lighter and lighter. While a side cloth is a thin and lightweight fabric, a problem arises that the side cloth is rubbed against, for example, grass or trees, or a rucksack during mountain climbing or the like when used for outer clothing, and a down or feather may leak from the surface of a woven fabric due to degradation such as tear of the surface or fluffing.
Also for rainwear, a problem arises that the surface thereof is rubbed against a rucksack or the like and torn during mountain climbing, and raindrops permeate through the front fabric face. Further, a woven fabric resistant to abrasion against another object is required for rucksacks, tents, and the like used for mountain climbing, camping, and the like. Thus, for outdoor clothing and materials, a woven fabric that is thin, lightweight, and further excellent in abrasion resistance, is required.
For example, Patent Literature 1 discloses a method in which abrasion properties of a material for clothing is omnidirectionally improved by specifying a range of an intrinsic viscosity of polyester fibers of a woven fabric and setting crystallinity of the polyester fibers to be in a certain range in order to obtain an abrasion-resistant woven fabric. However, in this method, although it is certain that abrasion properties are improved, it is difficult to maintain characteristics such as down-proof properties and low air permeability required for a side cloth of down jackets, rainwear, articles for mountain climbing, and the like.
For a side cloth of ultralight down wear and rainwear to which the present invention is mainly applied, an ultrathin and lightweight woven fabric is obtained by using fine filaments. Further, the woven fabric has a high density to close gaps between filaments in order to prevent spouting of batting and entering of water. Also as a fine filament used for obtaining low air permeability, a filament which has a relatively low single yarn fineness, and includes the increased number of fibers, is used. However, in a case where fibers having a low single yarn fineness are used, the fibers are likely to be damaged due to rubbing when used and consumed. Particularly in these applications using fine filaments, a problem that is concerned directly with reduction of the strength of the woven fabric, or degradation of air permeability, arises.